News:

If you are a member of the Team on BOINC you still need to register on this forum to see the member posts.  The posts available for visitors are not posted to much by members.
 Remember to answer the questions when Registering and also you must be a active member of Team BOINC@AUSTRALIA on BOINC.

Main Menu

Project Overview

Started by Cruncher Pete, May 21, 2009, 11:59:52 AM

Previous topic - Next topic

Cruncher Pete

   





Project Summary
The hash function SHA-1 (see e.g. wikipedia) is one of the most important cryptographic building blocks used today. It was designed by NSA and put forward as a standard by NIST in 1995. Browsing the Web, administering severs via ssh, or storing and comparing passwords are just a few examples where SHA-1 is used and trusted by many of us on a daily basis.
Most predecessors of SHA-1 were broken, i.e. collisions have been found:
The German cryptographer Hans Dobbertin found a pair of colliding messages for MD4 in 1996.
In 2004, a group of Chinese researchers around Prof. Wang found the first collisions for MD5 and RIPEMD.
Independently and shortly afterwards a French group around Antoine Joux reported a collision for SHA-0 (or alternatively called SHA), the direct predecessor of SHA-1.
So far nobody could show a collision for SHA-1, since SHA-1 is much more resistant against these style of attacks.
However, researchers define variants where they reduce the number of steps. The variant which comes closest to the real SHA-1 for which a colliding message pair was found is SHA-1 reduced to 70 out of 80 steps. Note however that the workload grows exponentially with the number of steps. This implies that a hash function for which there is an attack on a variant with only half the number of steps is by no means 'half broken'.
As soon as the input to a hash function can get longer than the output, collisions between inputs are unavoidable. For a hash function with n bit output size, a birthday attack (see e.g. wikipedia) requires about 2n/2 hash operations to find a colliding message pair. A dedicated attack, on the other hand, tries to exploit the inner working of the hash function. The SHA-1-Collison Search Graz Project is of that type.

Applications
The following platforms are supported:

Microsoft Windows x86    (32bit)
Linux x86                       (32bit)
Linux x86_64                  (64bit)

Connecting to SHA1 Collision
The project's Home Page is located at:http://boinc.iaik.tugraz.at/sha1_coll_search/
SHA1 Collision Search is also listed in the various BOINC Account Managers and you can join the project through them directly.
Don't forget to join BOINC@Australia Team following your registration.

Statistics
View our Team Members List and their current score here
View detailed BOINCStats for our SHA1 Collision Team here